MIdterm exam review Chem

ductile, malleable

metallic

brittle

ionic and covalent

delocalized electrons

metallic

made up of ions

metallic and ionic

high melting points

metallic and ionic

low melting points

covalent

only has positive ions

metallic

brass

metallic

MgBr2 is an example of…

ionic

P2O5 is an example of

ionic

sharing electrons

covalent

conducts as a solid or a liquid

metallic

never conducts

covalent

Conducts if melted or in a solution

ionic

alloy

metallic

Kilo

10³, 1000 m = 1km

Centi

10^-2, 100 cm = 1m

Milli

10^-3 1000 mm=1 m

Micro

10^-6 1,000,000micro=1m

decimeters

1m =10 dm

1mL=?

1cm³

What is the definition of accuracy

Refers to how close the measured value is to the actual value

Precision

Refers to how close a series of measurement are to one another or how reproducible they are

Atomic radius pattern

the distance from an atoms nucleus to its outermost electron. And get smaller across a period so from left to right and stronger nuclear pole on the same shell, making the biggest atoms in the bottom left and the smallest on the top right like helium of this periodic table due to the increasing protons pulling electrons closer. So down a group atomic radius increases while across a period atomic radius decreases.

Ionization energy

the minimum energy needed to remove an electron from a gaseous atom or ion, creating a postive ion. Generally increases across a period and decreases down a group on the table with the noble gases, having the highest value values due to stable electron shells, which is measured in units like kilojoules over moles or electron volts, and alkaline metals have the lowest ionization energy because they readily lose their single valence electrons easily.

Law of multiple proportions

when there are fixed portions of compounds, doesn’t have to be the same

Law of definite proportions

constant composition

What is the definition of an orbital

The regions surrounding the nucleus with high probability of finding an electron

Democritus

introduced the idea of atoms , the point matter could not be cut into any smaller pieces

Dalton

atomic theory is nicknamed billiard ball model

1)all substances are made of atoms(smallest particle, cannot be divided, cannot be created or destroyed)

2)all atoms of same element are alike and have same mass/atom of different elements are different and have different masses

3)atoms join together to form compounds, aways consisting of same kinds of atoms in same ratio

it falls short because its too simple

Thomson

was first to theorize the presence of electrons.

Cathode Ray experiment

Used sealed glass tube with most air evacuated voltage applied. This caused a beam of particles to flow down the tube from the cathode. This tested properties of particles. Particles were deflected away from the negative charge and the plates equals cathode raise were negatively charged, and very small. This also determine mass to charge ratio.

What is Thompson’s atomic theory named the

The plum pudding model

Rutherford was credited for discovering the

Nucleus

Explain Rutherford’s gold foil experiment

Fire, thin stream of alpha particles at the sheet of pure gold. Assumed Alpha particles would pass through because Thompson’s model assumed positive charge was spread out and would allow Alpha particles through however, this did not happen. Some alpha particles were deflected because a positive charge must be concentrated

Rutherford’s atomic theory was nicknamed

Nuclear model

What is the definition of matter?

Anything that has mass and takes up space

Homogeneous

Appears uniform throughout

Heterogeneous

Do not have a uniform composition

Element

Simple type. Just one type of atom show elements on the periodic table.

Compound

Consists of two or more elements always chemically combined in the same proportion compounds are considered molecules, but not common molecules are considered compounds

Solution

Made up of two parts so you and solvent. Solute is made up of small particles that can pass through filters or semi permeable membranes so a homogeneous mixture.

Colloid

A mixture having particles that are moderately large and can pass through filter, but cannot go through semipermeable membranes and it is a heterogeneous mixture

Suspension

A mixture with solute particles that are large enough and heavy enough and settle out and be retained by both filters and semipermeable membranes

Pure substance

Matter that has one type of atom, molecule, or compound

Mixtures

Two or more different substances that are physically mixed

What are intensive properties?

Independent of the amount of substance. It doesn’t matter how much you have these properties stay the same so color, boiling point, density.

What are extensive properties?

Depends on the amount of substance like mass length and shape

Electronegativity

The measure of an atoms tendency to attract shared electrons in a chemical bond. This is a crucial property that indicates bond polarity and chemical behavior flooring is the most electronegative and alkali metals are the least, following periodic trends of increasing left to right and decreasing from top to bottom, it is measured on scales.